Check out O'Brien (Siobhan Finneran, second from left) in the red dress! She's with fellow actors Lesley Nicol (left), Laura Carmichael and Thomas Barrow (right) at London's National Television Awards in 2012.

Check out O'Brien (Siobhan Finneran, second from left) in the red dress! She's with fellow actors Lesley Nicol (left), Laura Carmichael and Thomas Barrow (right) at London's National Television Awards in 2012.

Photo: Ian Gavan, Getty Images

Check out O'Brien (Siobhan Finneran, second from left) in the... Photo-4019629.55029 - GreenwichTime

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You know her as the Dowager Countess. But here's actress Maggie Smith lin 1963, long before the role came along.

You know her as the Dowager Countess. But here's actress Maggie Smith lin 1963, long before the role came along.

Photo: Stan Meagher, Getty Images

You know her as the Dowager Countess. But here's actress... Photo-4019630.55029 - GreenwichTime

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Maggie Smith as the Dowager Countess of Grantham. On top of already having two Oscars, Smith won two Emmys for her work in 'Downton Abbey.' She has been a longtime actress on stage and screen.

Maggie Smith as the Dowager Countess of Grantham. On top of already having two Oscars, Smith won two Emmys for her work in 'Downton Abbey.' She has been a longtime actress on stage and screen.

Maggie Smith as the Dowager Countess of Grantham. On top of already... Photo-4019631.55029 - GreenwichTime

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Elizabeth McGovern's life couldn't be more different that of Lady Grantham, the character she plays. McGovern fronts the country/folk rock band Sadie & The Hotheads.

Elizabeth McGovern's life couldn't be more different that of Lady Grantham, the character she plays. McGovern fronts the country/folk rock band Sadie & The Hotheads.

Photo: Christie Goodwin, Redferns Via Getty Images

Elizabeth McGovern's life couldn't be more different that... Photo-4019632.55029 - GreenwichTime

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Elizabeth McGovern has also a longtime movie actress. She's pictured in 1982.

Elizabeth McGovern has also a longtime movie actress. She's pictured in 1982.